O2 as initiator of autocatalytic degradation of hemicelluloses and monosaccharides in hydrothermal treatment of spruce

Jussi V. Rissanen, Lucas Lagerquist, Kari Eränen, Jarl Hemming, Patrik Eklund, Henrik Grènman*

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

2 Citations (Scopus)
46 Downloads (Pure)

Abstract

The influence of oxygen (0–50 bar) on the molar mass and composition of hemicelluloses after hydrothermal treatment of spruce chips was studied in a batch reactor setup at 130 °C–160 °C. Purified galactoglucomannan was studied as a reference. The dissolved oxygen enhanced significantly the depolymerization of hemicelluloses from over 15,000 g/mol to 180 g/mol (monomers) as well as promoted acids formation from the monosaccharides. About 2–3 times faster depolymerization was observed already with rather low amounts of oxygen (2–8 bar), while the kinetics of depolymerization was significantly slower in inert atmosphere. The decrease in pH from neutral to as low as 2.5 lead to an autocatalytic effect on the polysaccharide hydrolysis and the consecutive reactions of monosaccharides. The results emphasize the importance of performing hydrothermal treatment under inert atmosphere if large polymeric hemicellulsoses are desired or if monosaccharides are targeted in hydrolysis of hemicelluloses. If autocatalysis begins, it is difficult to stop.

Original languageEnglish
Article number119740
JournalCarbohydrate Polymers
Volume293
DOIs
Publication statusPublished - 1 Oct 2022
MoE publication typeA1 Journal article-refereed

Keywords

  • Depolymerization
  • Galactoglucomannan
  • Hemicelluloses
  • Hydrothermal extraction
  • Kinetics
  • Oxygen

Fingerprint

Dive into the research topics of 'O2 as initiator of autocatalytic degradation of hemicelluloses and monosaccharides in hydrothermal treatment of spruce'. Together they form a unique fingerprint.

Cite this